1. Field of the Invention
The present invention is generally related to a ZIF (zero insertion force) socket, and particularly to ZIF socket having a retention means formed on a base of the socket to retain effectively a lever of the socket in a vertical position with regard to the base.
2. Description of the Related Prior Art
The CPUs are more and more popular in the computer industry. As well known, the CPU is commonly connected to a mother board through a ZIF socket which is directly mountably soldered on the mother board. It is noted that the ZIF socket generally includes a base securely mounted onto the mother board, and a cover slidably moved with regard to such base by way of lever means whereby the CPU may be loaded onto the socket in a ZIF status when the lever is in a vertical position and the socket is in an open state, and the conductive pins of the CPU can engage the corresponding contacts in the socket for operative signal transmission when the lever is in a horizontal position and the socket is in a closed state. Prior art ZIF sockets are disclosed in U.S. Pat. Nos. 5,722,848, and 5,167,515. A related art is shown in FIG. 5, which discloses a ZIF socket 1 comprising a base 11, a cover 12 slidably mounted to the base 11 and a lever 13 including an actuation handle 131 and a cam shaft 132 joined with each other at an angle. The cover 12 has an upper half channel 120 and the base 11 has a bottom half channel 110 wherein the upper channel 120 joins with the bottom channel 110 to form a fall channel enclosing the cam shaft 132 therein. In assembly, the can shaft 132 is received in the bottom half channel 110 and the handle 131 is exposed to one side of the base 11. A CPU (not shown) is loaded onto the cover 12 under zero insertion force when the lever is in a vertical position. After the handle 131 is driven to a horizontal position, conductive pins of the CPU will engage with conductive means of the socket 1 and the socket 1 is in a closed state.
This type of socket includes several disadvantages. First, it is difficult to load the cover 12 onto the base 13 if the lever 13 has shifted from the vertical position a certain angle and the CPU cannot be loaded onto the socket under a zero insertion force. Secondly, the cover 12 and the base 11 will nip the pins of the CPU tightly if the handle 132 of the lever 13 so shifts from the vertical position that the cover 12 slides a distance against the base 11. Furthermore, the cam shaft 132 will push the cover 12 a certain distance from the right position in a horizontal direction for being fixed on the cover 12 straight. Therefore the CPU is difficult to be pulled out and pins of the CPU will have a tendency of being damaged.
Hence, an improved ZIF socket having retention means is required to overcome the disadvantages of the prior art.
Therefore, an object of the present invention is to provide a ZIF socket having retention means directly formed on a base of the socket to effectively retain a lever at a right position relative to the base.
To achieve the above-mentioned object, a ZIF socket in accordance with the present invention comprises a base defining a bottom half channel and a cover defining an upper half channel wherein the bottom half channel joins with the upper half channel to form a full channel enclosing a lever of the socket having a cam shaft and a handle. A retention means is fixed on the rear portion of the base, a resilient arm extends from top portion of the retention means forwardly formed a recess thereon. The handle is position by one side of the socket and can be retained by the recess in a right position with regard to the base.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.